Tracer for duplicating machines



Oct. 8, 1940.. o. LROSEN TRACER FOR nurLlcAwmwmAcapins Original Filed May 28, 1936 N v N5 w ll)! lllllwl 0 I INVENTOR.

oscAR E.ROSEN BY MEMI$7" I 7 ATTORNEYS Patented 06.8, 1940 UNITED STATES PATENT oFFlcE 5 Claims. -(o1. 99-62) The present invention relates totracers for duplicating machines and has among its objects one which eliminates the necessity for lateral or longitudinal displacement ofthe tip in order to .5 accomplish the reaction upon the cutter, such tracers being particularly useful in'reproducing from a flat template contacting the tracer point laterally, though not limited tosuch use, since the tracer likewise is operable through contact 10 with its end.

' Other objects will readily occur to those skilled in the art upon reference to the'following description and the accompanying drawing in which 1 showing theconductors attached.

Figure 2 is a longitudinal section through the tracer.

Figure Sisasection on linen-l6 of Figure '2.

of a part of the tracer.

Figure 5 is a section on line le -l9 of Figure 4. In the drawing, the tracer point 250 is shown as carried upon a shaft 251' freely rotatable in a 25 tubular housing 252- in suitable bearings 253 and 254, the shaft being movable endwise in' the former while thelatter 254 maintains the shaft against longitudinal movement outwardly of the housing. The inner end of shaft 2 -is prefer- 30 ably enlarged, bored axially and tapped as at 255 to receive .the screw threaded end of 'a "continuation shaft 255 and the'e'nd .of the latter .drilled diametrically to receive a pin 251 which extends through the walls of the tapped portion a of shaft 25\ through are shaped slots 25'. This arrangement permits a limited relative rotation between shafts 25] and 255.

' Relative rotation of shaft parts 25] and 255 is however prevented under'ordinar'y mnditions I by means ofa spring '2" surrounding shaft 255 and fixed thereto at one end through'a suitable collar 2". The other end of the spring 250 is fixed to shaft "I as at 252.v Suitable tension may be given toispring 250 by rotation of collar 1 45, 25! and fixing its position, as by a suitable set screw.

haft 2551s carried in a suitable bearing an,

slidably axially in the housing 252 and has mounted thereon a cap 255', perforated at its end 50 to permit passage ofa pin 2'1, the headed end of which is pressed axially outward by means of a spring 255. The cap 2 is prevented from rotation on shaft 255 by means-of a cotter pin 2". Fixed across the end of cap 205 is a yoke 55 element 21! to which are pivoted the arms ,2"

Figure 1 is s. 'viewin elevation of the-tracer I Figures is a section showing a modified form forward position. will; therefore, allow the weights to move inwardly and lengthen the distance between the 35 shaft of a small electric motor 215 mounted withinan enlarged continuation 216 of housing 252. At the rear end of the motorhousing 21B is. mounted a small casing 211 enclosing the electric contacts operable through the 'endwise movement of the shaft 214, the latter carrying an insulated member I84 against which is spring 10 pressed a movable contact carrier 205. This latter is connected to the-conductor 201 and in moving may contact either of the stationary contacts I98 01' I89, these being connected with the conductors 200 and 20011, respectively.-

In the operation of this form of. tracer, the motor 215 of very low horsepower rotates the tracer tip at high speed but with small force, and, if a resistance, such as frictional contact,

be reduced. The momentary reduction of the .speed of rotation of the tip will cause a relative.

rotation between the parts l and 255 of the shaft, thereby lengthening the latter. when this happens, shaft part 25l cannot move be- 25 cause of the thrust bearing .254, so the part 25 moves backward and thereby moves the armature shaft which, in turn, -operates the contacts in thehousing 211.

Further, when the shaft 255 is being rotated at high speed, the governor (210-213) is thrown outward, maintaining the armature shaft in its Slowing down of the governor armature shaft and cap 256, thereby moving the armature shaft backward and thus operating the contacts.

While Figure 2 shows both the spring device 280 and' the governor for producing the same result, either may be used by itself.

In Figure 4 there is shown another form of construction for causing lengthening of. the shaft when its two portions are relatively rotated.

'In this form, the two parts 15m and 355 (the 45 part in being shown as an enlargement at the end. of part 350 are provided with sleeves 352 and 358, respectively, which abut as at 351 and are notched as at 355 to provide an angular hole in which lies a ball I53. g o

The sleeves I52 and 356 are fixed-to their respective shaft portions by suitable pins or screwsv and in such position that the end of one shaft part extendsinto the sleeve upon the other partto act as-a pilot and also to back up the ball 35! 56 I in the hole 358. A third sleeve 35! overlies the junction of the other two and is fixed to sleeve 352 so as to act as a retainer for the ball 353. This sleeve 359 is also preferably notched at one end as at 360 to cooperate with a pin I in sleeve 356, the pin and notch serving to limit the relative rotary movement of the several parts.

The present case is a division of Serial No.

82,362, filed May 28, 1936, for "Profiling machines and in the name of the present applicant.

the parts thereof extending from the housing, a

tracer point carried by said extension, means for rotating the other'part of said shaft, and coupling means for said shaft parts, said coupling means including means interposed between said ends for moving said ends relatively longitudinally upon retarding the rotation of one of the shaft parts, and electric contact means actuable by the longitudinally movable shaft part.

3. A tracer for pattern controlled reproducing machines comprising a housing, a divided rotatable shaft mounted therein and having one of the parts thereof extending from the housing, a tracer point carried by said extension, means for rotating the other part of said shaft, and coupling means for .said shaft parts, said coupling means including male and female threaded shaft portions coacting to couple said portions in driving relation, resilient means tending to maintain the shaft portions in normal driving relation but allowing relative rotation of the shaft parts, and means to limit such relative rotation, and electric contact means in operative relation to one of said shaft parts. a 4

4. A tracer for pattern controlled reproducing machines comprising a housing, a divided rotatable shaft mounted therein andhaving one of the parts thereof extending from the housing, a tracer point carriedby said extension, means for rotating the other part of said shaft,- fiyball governor means connecting said parts in driving relation and constituting speed responsive meansv for 'moving, the shaft parts relatively longitudinally, and electric contact means operatively connected to one of the shaft parts.

5. In a tracer for pattern controlled reproducing machines an electric motor having its rotor shaft mounted for limited longitudinal movement, electric contact mean'sadapted to be actu-- ated by the longitudinal movement of said shaft, a tracer finger rotatably mounted and adapted to be rotated by said motor but fixed against longitudinal movement and coupling means for said' motor and finger constructed and arrangedto cause longitudinal movement of the said rotor shaft upon retardation of the rotation of said finger. 1

- OSCAR E. ROSEN; 

